Rotary machine sieve of wire gauze particularly for paper machines



Patented Apr. 2, 1929.

UNITED STATES PATENT "OFFICE. A

ALBERT nnsmrmns, or Essa- 1, noun? mcimm SIEVE or m GAUZE mn'rrcnnannx Ion rum; nacnnms.

1J0 Drawing. Application and lay 18, 1926, Serial m. 110,009, and in am, October as, 1924.

In the endless sieves or wire cloths of paper making machines the rapid wear andtear to which they are subjected, is principally caused by the friction produced by the various rollers over and around which they are passed under working conditions and also that produced by the suction boxes and cleaning ap liances. The wire cloths are also'continual y bent and straightened again intheii' passage round the rollers and are further-f more subjected continuously to tensile stralns in the direction oftheir length. In consequence ofthese actions particularly the incessant bending and straightening, the material of the wire cloth becomes gradually destroyed, and it is the war s in particular of the wiregauze-which su er under these circumstances, whereas the destructiveaction on the wires of the ,weft is less.

The wires hitherto commonly used for the wire cloths of paper making machines are mostly composed of bronze or a material similar to bronze, and these wire cloths con- 1 sequently possess'only a very limited length of life. The use of steel wires, although they are considerably stronger than the aforesaid ient as this material-rusts, whereby not alonewires and better able to resist the above mentioned mechanical influences, 1s not convenis its destruction accelerated, but the material treated easily becomes contaminated. Recently highly alloyed improved steels have been produced, which do not rust and in addition to great hardness-possess an extra ordinary degree of toughness, whereby they are afforded a power of resistance to breakage and wear which is not possessed by any other material. It has also been already proposed to make wire .cloths for papermaking machines of improved steel, as its pre-eminent properties make it much more suitable for the purpose-than any other kind of wire; Its use is however not by any means economical, because its market price is so high .(approximately ten times that of bronze when in the form of 5 wire gauze) that the advantages of the lon er life of the wire cloths are to a considera 1e amount discounted. I The object of 'the present invention is to make the use of the above mentioned hi h grade improved steel more economical or the manufacture of machine sieves or wire cloths and the invention consists in making the wires of the warp only of the gauze of a highgrade non-rusting steel which possesses special powers of resistance to wear, while for theweft which is subjected to less strain wires ofa lower quality, such for example as the bronze wire which-has hitherto been used is employed.

' According to the present invention machine sleve's are likewise of longer lengthof llfe than such in which both the warp and weft are made ofhigh grade. improved.

They are however as their price is only about ths of that of the latter, considerably cheaper to provide than these and consequently-afiord very ,yantages The improved steels are mainly highly alloyed chromium nickel steels. These are made of different composition according to the special properties which it is desired to considerable'economical adand 0,10,4% C- They may beused as the material for warp wires for the manufacture of the subject matter of the application. It is obvious of course that-the properties of steels so differently alloyed will differ greatly and also the cost of maintenance. Among the chromium nickel.

steels produced on a manufacturing scale two groups may be selected substantially which possess considerably difi'erent chemical and physical properties in addition to differences of structure. Thecfirst group of a Martensite or 'Troostite texture contains steels with a medium amount of chromium and a small amount of nickel. To'the second group with an Austenite texture belong steels containing'a-large amount of chromium and a medium amount of nickel. These are distinguished by great power of resist-' ance to corrosion of every kind and by a very great power of resistance to wear and are particularly suitable as a material for warp wires of the kind herein referred to. The steels of. the first group may also be used for the manufacture of war wires as the can be made rust proof. A though superior to obtain andthey may also have small quantiwear and tear that is possessed by the steels of the second group. On the other hand they are considerably cheaper to manufacture than these. Where high grade nickel steel is used for warp wires, these steels may also be used for the weft.

The present invention may also be used for rotary sieves .or wire cloths for other machines than paper making machines as for example for the sieves of machines for the manufacture of coal dust such as is used for coal dust fire furnaces.

Claim:

Wire gauze for paper making machines comprising warp wires of strong, tough, nonrustlng steel and weft wires of lower quality more easily bendable non-rusting material.

' In testimony whereof the foregoing specifi- 20 cation is signed at Cologne, this 27th day of pril, 1926.

ALBERT ELSENHANS. 

